1. Field of the Invention
The invention relates to quick release mechanisms for detachable hitches used on heavy duty industrial transport carrier frames, particularly manufactured housing carrier frames.
2. Description of Related Art
Trailer hitch assemblies for industrial transport carrier frames and manufactured housing carrier frames are known in the art. However, in cases where the hitch assemblies are temporarily mounted with flanges and bolts, the removal of such assemblies are very difficult, cumbersome and potentially injurious due to the inherent weight of the steel beam used to manufacture the hitch assemblies.
Hitches in common use today in the mobile home/manufactured housing industry as well as in other industries using carriers require that nuts and bolts be removed from underneath the carrier frame requiring workers to crawl under the hitch assemblies. In some cases where room to crawl underneath is limited and the manufactured housing or mobile home has to be lifted to be placed on a foundation, a crane lifts the manufactured housing or mobile home and while it is elevated, workers dismantle the hitch assembly while standing under the carrier frame.
Generally, each beam used in a prior art hitch assembly is approximately 8 feet long. A 12 inch beam may weigh about 11.8 pounds per linear foot, a 10 inch beam may weigh about 8 pounds per linear foot, and a 8 inch beam may weigh about 6.8 pounds per linear foot. Therefore, after a carrier is in a desired position, removal of the hitch assembly can require the handling of about 200-250 pounds. This often has to be done by one person who must in some cases crawl under the assembly to remove the fastening bolts. A mishap causing temporary disabling injuries is not uncommon.
Known related art includes hitch assemblies as depicted in FIGS. 1a and 1b. In FIG. 1a, two of the beam members 12 forming the A-frame of the hitch assembly 18 are cut. The cut legs or beam members 12 are then permanently welded at 16 to the inside of the carrier frame 14, that is, the cross member. Slots 28 are cut in the cross member of the carrier frame 14 and gusset plates 20 are inserted through each slot 28 and 4-6 bolts 22 are used to attach the gusset plates 20 to the beam member 12 inside the carrier frame 14. The gusset plates 20 remain extended forward of the carrier frame 14 so that the hitch tongue portion of the hitch assembly 18 can be bolted to the gusset plates 20. Although this type of hitch assembly provides for a reduced weight assembly, a worker still has to deal with 8-12 bolts in removal of the hitch assembly from the carrier frame.
FIG. 1b depicts another prior art hitch assembly 24, which forms an A-frame with 8-9 foot beams 12 for each leg. The beam upper flanges have flange plates 26 welded at about the end of each beam 12 and at an intermediate location. Each flange plate 26 is placed to line up with a carrier frame 14 cross member where 4 bolts (not shown) are used to secure the hitch assembly 24 under the carrier frame 14.
None of the devices in the above references provide a quick release mechanism which can be used with a reduced weight hitch assembly to provide a safe dismantling of the hitch assembly without having to crawl under the hitch assembly and carrier frame, and which can be used with the above described lower profile carriers using portable axle and tire assemblies. An object of the present invention would provide a device which would be safer to dismantle without having to crawl underneath a carrier frame and would reduce labor costs in the form of time required to separate the tongue portion of a hitch assembly in the field. Where the hitch can be reused again, several hundreds of dollars can be saved by recycling the same hitch assembly for future jobs.
The present invention is a quick release mechanism for a detachable hitch assembly for use on manufactured housing transport carrier frames, usually subfloors to the manufactured housing. The invention is also adaptable to other heavy industrial transport carrier frames where it is desirable to remove the tongue portion of the hitch assembly. In addition, the invention may be used to interconnect transport carrier frames so they may be transported in tandem.
The invention is a quick release mechanism which takes an A-frame tongue portion of a hitch assembly or an X-frame butterfly hitch assembly, and modifies the end beams, typically I-beams, of the hitch assemblies with end plates. Near the top and bottom of the two ends plates are welded pipe segments horizontally oriented and having a hollow interior to receive a quick disconnect pin, for example, an approximate xc2xe inch diameter pin. Although the quick disconnect pin is preferably a round rod, other shapes are contemplated such as square, hexagonal, etc. The hollow interior of the pipe segments would be shaped to correspond to the shape of the pin used.
A hitch assembly attachment plate is then provided which is typically welded to the front face of the carrier frame cross member, thereby essentially making it integral to the carrier frame. The hitch assembly attachment plate also has two welded pipe segments horizontally oriented and having a hollow interior to receive the quick disconnect pin near the top of the hitch assembly attachment plate and two similar welded pipe segments near the bottom of the hitch assembly attachment plate. Each pipe segment on the attachment plate and each on the A-frame end or X-frame end plates are approximately the same length. The pipe segments on the hitch assembly attachment plate are spaced apart to allow the pipe segments on the A-frame or X-frame end plate to be placed between the hitch assembly attachment plate pipe segments so as to form what appears to be a hinge assembly. The hollow interior of each pipe segments are also aligned to receive the quick disconnect pin through the pipe segment starting near one edge of the hitch assembly attachment plate through the pipe segment in the A-frame end or X-frame plate and continue through the pipe segment ending near the other edge of the hitch assembly attachment plate.
In one embodiment of the invention, the hitch assembly attachment plate is not used and the pipe segments normally associated with the hitch assembly attachment plate are instead welded directly to the carrier frame cross member and aligned to receive the quick disconnect pins as described above.
In a typical application of the invention, the hitch assembly attachment plate may be about 12 inches wide by 10.5 inches wide and each pipe segment may typically be about 4 inches long and large enough to accommodate the pin size, usually xc2xe inch diameter.
Other size hitch assembly attachment plates and corresponding pipe segment sizes, including pin sizes may be used depending on the workloads and desired safety factors involved.
The quick disconnect pins are typically U-shaped with an outwardly extended handle portion extending from one of the legs of the U-shaped pin. The portions of the U-shaped pin and handle portion which do not extend inside a pipe segment need not be the same diameter as the pin portion entering the interior of the pipe segments. They may be made from smaller bar stock and welded or otherwise attached to the pin portion entering the pipe segments. The pin portion entering the pipe segments are sufficient to allow a relatively snug fit, yet with sufficient tolerance to allow the pin to be inserted and removed with little resistance.
When a quick disconnect pin is inserted to engage the hitch assembly frame end plate to the hitch assembly attachment plate, the handle of the pin is rotated out of the way against an inside flange portion of the hitch frame beam or against the inside surface of the hitch frame end plate. The handle is retained in position with a retainer clip. A pair of retainer clip attachment plates with eyelets are welded so as to extend from a surface of the hitch frame beam, which can be from the inside of the flange or main channel member, or from the inside surface of the end plate. The pair of retainer clip attachment plates are aligned and spaced apart to rotate the handle in between the pair of retainer clip attachment plates so that a pin on the retainer clip may be inserted through one eyelet over the handle and through the second eyelet and the clip then secured to stop the handle from rotating out of position. This means of using a retainer clip can be used for each handle individually or one retainer clip may be used to retain two handles simultaneously.
The materials for the quick release mechanism may be carbon steel, stainless steel and other suitable metallic materials.